Rock drill



July 27, 1926. 1,593,606

- F. M. SLATER ROCK DRILL Filed June 24, 1925 5 ATTOR 'Y Patented July 27, 1926.

umree stares re atta e aren't FRED M. SLATER, OF EASTON, PENNSYLVANIA, ASSIGNOR '20 INGERSGLL RAND COM- PANY, F JERSEY CITY, NEW JERSEY, A CORPORATEION OF NEW JERSEY.

R0 CK DRILL.

Application filed June 24, 1925.

This invention relates to fluid actuated rock drills of the hammer type, but more especially to valve mechanism for such drills.

The objects of the invention are to enable two automatic fluid actuated valves to control the distribution of pressure fluid to the cylinder, one valve for controlling the inlet and another valve for controlling the exhaust, and also the kicker ports for the inlet valve.

Another object of the invention is to enable the exhaust controlling valve to be located within the cylinder in the form of a sleeve within which the piston reciprocates.

The invention is shown in one of its preferred forms in the accompanying drawings, in which- Figure 1 is a longitudinal sectional elevation of a rock drill having the invention ap- 2 plied thereto, and

Figure 2 is a similar view with the parts in a different position.

The drawings illustrate the invention in connection with a rock drill of the hand held or jackhammer type, although the invention may be applied to any suitable type of rock drill.

Referring to the drawings, the cylinder A is provided with the reciprocating hammer piston B having the forward fluted shank C adapted to impart blows of impact to the drill steel D. In this instance, the machine is provided with automatic. rifle bar rotation, the rifle bar E and rotation ratchet F and ratchet ring G being indicated. A suitable handle H for the machine is provided and the parts are held together by the usual side bolts (not shown).

Pressure fluid is supplied to the inlet J in the valve chest K and pressure fluid is distributed to each end of the cylinder through the ports L and O by means of the inlet valve P having the central enlarged head Q, and the reduced ends R and S, which control the passages T and U. The central head Q of the valve operates in the chamber V having a vent T to atmosphere and kicker ports X and Y leading from the chamber V permit the actuation of the valve in accordance With the reciprocation of the piston.

The cylinder A is provided with the exhaust ports a and 6 opening into the grooves 0 and d in the cylinder and a sleeve valve Z Serial No. 39,166.

reciprocates within the cylinder between the stops formed by the back head 6 and the shoulder f at the forward end of the cylinder. This sleeve valve Z is provided with the grooves g and it having the apertures y' and 7e extending through the walls of the valve for cooperation with the exhaust ports a and b and also with the picker ports X and Y.

In the operation of the device let it be assumed that the piston is first in the position indicated in Figure 1 at the rearward end of the cylinder and is moving on its forward stroke, in which case the valve V will be in its forward position as indicated. Pressure fluid from the inlet J will then pass over the end B of the valve to the inlet port L and thence to the rearward end of the cylinder to drive the piston forward. The sleeve valve Z will be in its forward position and the exhaust port I) in the cylinder will be open as shown for exhausting the forward end of the cylinder. The valve P will be held in its forward position, due to the pressure of live motive fluid on the end or face R of the valve. As the piston moves on its forward stroke and before the exhaust port I) is fully closed by the piston head, the rearward groove 9 in the sleeve valve Z will have been uncovered by the rearward end of the piston, so that pressure fluid under working pressure will be supplied through the kicker port X against the forward face of the central valve head Q, of the valve which will throw said valve rearwardly to the position indicated in Figure 2, supplying live pressure fluid through the passageU and port- 0 at the forward end of the cylinder to drive the piston rearwardly. The sleeve valve Z is also thrown rearwardly, due to compression and the pressure of the live motive fluid so that the parts take the positions indicated in Figure 2.

As the piston moves rearwardly, the groove h in the sleeve valve Z and the ports 79 in said valve are uncovered before the exhaust port a atthe rearward end of the cylinder is fully closed by the piston so that pressure fluid under working pressure is supplied through the kicker port Y to the rearward face of the center head Q of the valve which throws the valve forwardly again and live pressure fluid entering the rearward end of the cylinder again throws the sleeve valve Z forwardly. From this point the cycle is repeated.

I claim:

17 In a fluid actuated rock drill of the hammer type, the combination of a cylinder and reciprocating piston, a valve chest, a fluid actuated inlet valve therein, exhaust ports in the cylinder, a fluid actuated sleeve valve surrounding the piston controlling said exhaust ports, and means for controlling the inlet valve by movement of said piston.

2. In a fluid actuated rock drill of the hammer type, the combination of a cylinder and reciprocating piston, 21 valve chest, a spool valve in said chest for controlling the inlet to both ends of the cylinder. a sleeve valve in the cylinder surrounding the piston head controlling the exhaust at both ends of the cylinder, and kicker ports for the said spool valve controlled by said sleeve valve.

In testimony whereof I have signed this specification.

FRED M. SLATER. 

